Propeller power transmission device for 1-engine, 2-shaft vessel

ABSTRACT

A propeller power transmission device according to the present invention comprises an input shaft  9  connected to a drive shaft  7  of an engine  3  via a coupling  8 ; a pair of right and left output shafts  12  and  13  connected to the right and left propeller shafts  5  and  6  via couplings  10  and  11 , respectively; a gear train comprised of gears  20  to  30  for transmitting the power of the input shaft  9  to each of the output shafts  12  and  13  through clutch mechanisms  14, 15, 16  and  17 , and causing the output shafts to undergo forward or reverse rotation in response to switching between forward and reverse rotation clutch mechanisms; and a gear case  4  for containing the input shaft  9 , the output shafts  12  and  13 , the gear train of gears  20  to  30 , and the forward and reverse rotation clutch mechanisms  14  to  17.

FIELD OF THE INVENTION

The present invention relates to a propeller power transmission device for a 1-engine, 2-shaft vessel, in which a drive shaft of the engine has a pair of propeller shafts on the right and left sides.

BACKGROUND ART

Examples of a propeller power transmission device for a 1-engine, 2-shaft vessel for transmitting engine power by dividing it into left and right propeller shafts include a mode using bevel gears, which is disclosed, for example, in the specification of US Published Patent 2006/89062; and a mode using cylindrical (flat) gears, which is disclosed, for example, in the specification of Published Japanese Utility Model 70999/1982.

In such power transmission devices, the gear mechanism for distributing engine power into the right and left sides is positioned immediately posterior to the engine, together with a rotational direction switching mechanism for selectively controlling the propeller shafts to undergo forward or reverse rotation, which is located at a point downstream from the power transmission device. However, this structure requires a larger number of components, and also requires separate attachment of plural mechanisms to the vessel. This has resulted in the problems of decreased workability and increased cost.

An object of the present invention is to provide a propeller power transmission device for a 1-engine, 2-shaft vessel, which solves the foregoing problems.

DISCLOSURE OF THE INVENTION

In order to attain the foregoing object, a first means of the present invention is a propeller power transmission device for a 1-engine, 2-shaft vessel in which a drive shaft for an engine has a pair of right and left propeller shafts, the propeller power transmission device comprising: a gear case; an input shaft that is supported by a bearing inside the gear case and that is combined with the drive shaft of the engine via a coupling; a pair of right and left output shafts that are supported by bearings inside the gear case and that are combined with the right and left propeller shafts, respectively, via couplings; and a gear train contained in the gear case for transmitting power of the input shaft to the pair of output shafts via a clutch mechanism, wherein the clutch mechanism includes a forward and reverse rotation clutch mechanism for switching the gear train so as to change rotation of the output shaft between forward and reverse.

The first means of the present invention may be arranged as a second means so that the gear train is comprised of a plurality of cylindrical gears and a single or two cone gears, and

shaft lines of the right and left propeller shafts are inclined by the cone gear(s) relative to shaft line of the engine drive shaft.

The first means of the present invention may be arranged as a third means so that the gear train comprises: a driving bevel gear fixed to the input shaft; a pair of driven bevel gears that are rotatably supported by an intermediate shaft extending orthogonally to the input shaft and that are engaged with the driving bevel gear; and a set of bevel gears for drivably connecting each of the output shafts with each end of the intermediate shaft intersecting with the output shafts; wherein a forward and reverse rotation clutch mechanism for selectively connects one of the driven bevel gears to the intermediate shaft so as to cause the intermediate shaft to undergo forward or reverse rotation.

The third means of the present invention may be arranged as a fourth means so that the clutch mechanism is provided on the intermediate shaft and includes a pair of power transmission clutches for transmitting or blocking power to the output shafts.

The fourth means of the present invention may be arranged as a fifth means so that each driven side of the power transmission clutches is provided with a brake for controlling the intermediate shaft.

The fourth means of the present invention may be arranged as a sixth means so that the intermediate shaft is comprises a first intermediate shaft, a second intermediate shaft and a third intermediate shaft; the first intermediate shaft is provided with a forward and reverse rotation clutch mechanism that rotatably supports the pair of driven bevel gears that engage with the driving bevel gear and selectively connects one of the driven bevel gears to the first intermediate shaft so as to cause the first intermediate shaft to undergo forward or reverse rotation; the second intermediate shaft and the third intermediate shaft include a set of bevel gears drivably connected to the respective output shafts; the first intermediate shaft connects to the second intermediate shaft and the third intermediate shaft via a gear train containing the power transmission clutches; and the clutch mechanism includes a rotational direction inverting clutch mechanism at a butt joint of the second intermediate shaft and the third intermediate shaft; the rotational direction inverting clutch mechanism being brought into operation only in a state where power transmission of one of the power transmission clutches is blocked.

The first means of the present invention may be arranged as a seventh means so that the gear train includes two or more speed-changing gear trains, each of which includes a driving, speed-changing gear and a driven, speed-changing gear, and the clutch mechanism further includes a speed-changing clutch mechanism for transmitting or blocking power from the driving, speed-changing gear to the driven, speed-changing gear in each speed-changing gear train.

The seventh means of the present invention may be arranged as an eighth means so that each driving, speed-changing gear is provided on the input shaft, and each driven, speed-changing gear is provided on a rotation axis disposed in parallel with the input shaft.

The first means of the present invention may be arranged as a ninth means so that the forward and reverse rotation clutch mechanism is comprised of hydraulic clutches, the propeller power transmission device further comprising a control lever for operating, by remote control, an output control device of the engine in conjunction with electromagnetic valves for controlling supply of a working oil to the hydraulic clutches.

The ninth means of the present invention may be arranged as a tenth means so that the speed-changing clutch mechanism is comprised of hydraulic clutches, the propeller power transmission device further comprising a switch for activating and deactivating the electromagnetic valves for controlling supply of a working oil to the hydraulic clutches.

The seventh means of the present invention may be arranged as an eleventh means so that the gear train includes a branch gear train for transmitting power of the input shaft by dividing it into the right and left output shafts, the speed-changing clutch mechanism is disposed closer to the input shaft than the branch gear train in the gear train, and the forward and reverse rotation clutch mechanism is disposed closer to the output shaft than the branch gear train in the gear train.

The eleventh means of the present invention may be arranged as a twelfth means so that each of the forward and reverse rotation clutch mechanism and the speed-changing clutch mechanism is comprised of hydraulic clutches, each axis for supporting each hydraulic clutch is provided with an oil seal case having a port connected to a working oil supply source on one end, and at least one internal oil path for supplying a working oil to the hydraulic clutch; the hydraulic clutches of the forward and reverse rotation clutch mechanism are supported by a pair of axes linearly arranged along a shaft line with their oil seal cases oppositely arranged; the hydraulic clutches of the speed-changing clutch mechanism are supported by an axis disposed orthogonally to the shaft line on which the axes for supporting the hydraulic clutches of the forward and reverse rotation clutch mechanism are arranged, with its oil seal case disposed in the vicinity of the oil seal cases of the axes supporting the hydraulic clutches of the forward and reverse rotation clutch mechanism.

The first means of the present invention may be arranged as a thirteenth means so that the forward and reverse rotation clutch mechanism separately operates the individual output shafts to undergo forward or reverse rotation.

According to the present invention, a clutch for inverting the rotation of a propeller shaft is integrated into a mechanism for dividing power into right and left propeller shafts. This arrangement reduces the number of components and improves mounting workability, thereby reducing costs.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view schematically showing a vessel with a propeller power transmission device for a 1-engine, 2-shaft vessel mounted according to the present invention.

FIG. 2 is a lateral view of FIG. 1.

FIG. 3 is a vertical cross-sectional view, taken along the line III-III in FIG. 1 and FIG. 2.

FIG. 4 is a cross-sectional view, showing details, taken along the line IV-IV in FIG. 3.

FIG. 5 is a cross-sectional view, taken along the line V-V in FIG. 3.

FIG. 6 is a cross-sectional view showing a modification of the propeller power transmission device of FIG. 5.

FIG. 7 is a hydraulic circuit diagram of the propeller power transmission device of FIG. 3.

FIG. 8 is a plan view schematically showing a vessel equipped with a propeller power transmission device for a 1-engine, 2-shaft vessel according to a second embodiment of the present invention.

FIG. 9 is a lateral view of FIG. 8.

FIG. 10 is an expanded cross-sectional view for schematically showing the second embodiment with an engine.

FIG. 11 is an expanded cross-sectional view showing a propeller power transmission device for a 1-engine, 2-shaft vessel according to a third embodiment of the present invention.

FIG. 12 is a lateral view showing the entire shape of a vessel equipped with a propeller power transmission device for a 1-engine, 2-shaft vessel according to a fourth embodiment of the present invention.

FIG. 13 is a cross-sectional view showing a propeller power transmission device for a 1-engine, 2-shaft vessel according to a fourth embodiment of the present invention.

FIG. 14 is a partial cross-sectional view, taken along the line XIV-XIV of FIG. 13.

FIG. 15 is a cross-sectional view of the propeller power transmission device of FIG. 13, showing details, taken along the power transmission path.

FIG. 16 is a hydraulic circuit diagram showing a propeller power transmission device according to a fourth embodiment.

FIG. 17 is a perspective view showing a control lever for operating the propeller power transmission device according to a fourth embodiment.

FIG. 18 is a vertical cross-sectional view showing a propeller power transmission device for a 1-engine, 2-shaft vessel according to a fifth embodiment of the present invention.

FIG. 19 is a partial cross-sectional view, taken along the line XIX-XIX of FIG. 18.

FIG. 20 is a cross-sectional view of the propeller power transmission device of FIG. 18, showing details, along a power transmission path.

FIG. 21 is a vertical cross-sectional view showing a propeller power transmission device for a 1-engine, 2-shaft vessel according to a sixth embodiment of the present invention.

FIG. 22 is a cross-sectional view, showing details, along the line XXII-XXII of FIG. 21.

BEST MODE FOR CARRYING OUT THE INVENTION First Embodiment

The following explains a first embodiment of a propeller power transmission device for a 1-engine, 2-shaft vessel according to the present invention, with reference to FIGS. 1 to 7. Throughout the figures, like components will be identified by like reference numerals.

FIG. 1 is a plan view schematically showing a vessel 2 equipped with a propeller power transmission device 1 for a 1-engine, 2-shaft vessel. FIG. 2 is a lateral view of the plan view of FIG. 1. As shown therein, a pair of propeller shafts 5 and 6 project respectively from the right and left sides of the gear case 4 provided in the front side of the engine 3. The edges of the propeller shafts 5 and 6 extend outward beyond the aft end of the vessel. As shown by the dashed line of FIGS. 1 and 2, the gear case 4 can be provided on the back side of the engine 3.

FIG. 3 is a cross-sectional view, taken along the line III-III in FIG. 1 and FIG. 2. FIG. 4 is a cross-sectional view developed along the line IV-IV in FIG. 3. FIG. 5 is a cross-sectional view, taken along the line V-V in FIG. 3.

The propeller power transmission device 1 comprises an input shaft 9 combined with a drive shaft 7 of an engine 3 via a coupling 8 made of an elastic joint; a pair of right and left output shafts 12 and 13 combined with the right and left propeller shafts 5 and 6 via couplings 10 and 11, respectively; a gear train having gears 20 to 30 for transmitting the power of the input shaft 9 to each of the output shafts 12 and 13 through clutch mechanisms 14, 15, 16 and 17, and causing the output shafts 12 and 13 to undergo forward or reverse rotation in response to switching between the forward and reverse rotation clutch mechanisms 14, 16 and 15, 17; and a gear case 4 for containing the entire of the input shaft 9, the output shafts 12 and 13, the gear train of gears 20 to 30, and the forward and reverse rotation clutch mechanisms 14, 16 and 15, 17.

The input shaft 9 is rotatably supported by a bearing 45 formed inside the gear case 4. The output shafts 12 and 13 are also rotatably supported by bearings 46 and 47, respectively, formed inside the gear case 4.

The forward and reverse rotation clutch mechanisms 14, 16 and 15, 17 can be realized by hydraulic clutches. Each of gears 21, 22, 27 and 28 is fixed to a supporting axis and has an outer drum in which a friction plate is implanted. Meanwhile, each of gears 23, 24, 29 and 30 is rotatably supported by a supporting axis and has an inner drum in which a pressure plate is implanted. This pressure plate allows the inner drum to engage with the outer drum by friction. The forward and reverse rotation clutch mechanisms 14, 16 and 15, 17 each having a friction plate and a pressure plate are engaged by friction in response to injection of a working oil into the piston chambers 40 to 43.

When the forward rotation clutches 14 and 15 are engaged and the reverse rotation clutches 16 and 17 are disengaged in such a gear train, the power of the input shaft 9 is transmitted in a manner such that the forward rotation output is transmitted to the output shaft 12 through the gear 20, the gear 21, the clutch 14, and the gear 23, and to the output shaft 13 through the gear 20, the gear 22, the clutch 15, the gear 24, and the gear 26. When the forward rotation clutches 14 and 15 are disengaged and the reverse rotation clutches 16 and 17 are engaged, the power of the input shaft 9 is transmitted in a manner such that the reverse rotation output is transmitted to the output shaft 12 through the gear 20, the gear 21, the gear 27, the clutch 16, the gear 29 and the gear 25, and to the output shaft 13 through the gear 20, the gear 22, the gear 28, the clutch 17, the gear 30, and the gear 26.

The gear train has the following composition. With the axes of the right and left propeller shafts 5 and 6 inclined with respect to the drive shaft 7 of the engine 3, the axes 21 a, 22 a, 27 a and 28 a supporting the gears 21, 22, 28 and 27 are arranged so as to be parallel with the drive shaft 7 and the input shaft as shown in FIG. 4, and the gear 23, the gear 25, the gear 24 and the gear 26 are formed of cone gears and the rest of the gears are formed of cylindrical gears, as shown in FIG. 5. The cone gear designates a gear specially shaped into an involute tooth, which is classified as a bevel gear engageable with a cylindrical gear. FIG. 6 shows an alternative layout in which a single cone gear 20 a is provided on the input shaft 9, together with a middle gear 50 engaged with the cone gear 20 a, so that the entire body of the gear case 4 is inclined. In this layout, as shown in FIG. 6, all gears of the gear train except for cone gear 20 a can be composed of cylindrical gears. This composition uses the least number of bevel gears, which are expensive and make noise.

FIG. 7 is a drawing of a hydraulic circuit for controlling clutches 14 to 17. The oil absorbed by a hydraulic pump 62 from the reservoir 60 via a filter 61 passes through the oil path 63, the forward/reverse switching valves 64 and 65, and the oil paths 66 to 69, before being supplied to the piston chambers 40 to 42 of the clutches 14 to 17 as a working oil.

The oil path 63 branches into the oil path 70, and the pressurized oil flowing into the oil path 70 then passes through a control valve 71, which is called a loose-fit valve, and an oil cooler 72. The oil pressure is then adjusted by a relief valve 73, and the oil passes through the oil path 74, before being supplied to the clutches 14 to 17 as a lubricating oil. The control valve 71 serves to reduce the shock due to the sudden engagement of the clutches 14 to 17. When the working oil is supplied to the clutches 14 to 17 in response to the switching between the forward/reverse switching valves 64 and 65, the control valve 71 first serves as a relief valve having a low pressure to release the working oil to the oil path 70. Then, as the oil amount supplied to the back chamber of the control valve 70 increases, the control valve 71 gradually narrows the oil path 70 with the restrictor 71 a. After a certain time, the control valve 71 is closed. With this function of the control valve 70, the clutches 14 to 17 gradually increase their force of engagement by friction. The clutch engagement shock is thus reduced.

In the illustrated example, the forward/reverse switching valves 64 and 65 are controlled by a monolever 77. The monolever 77 not only switches the forward/reverse switching valve 64 and 65 to cause the output shafts 12 and 13 to undergo forward or reverse rotation, but also operates the forward/reverse switching valves 64 and 65, for example, in a manner such that the output shaft 12 rotates in the forward direction and the output shaft 13 rotates in the reverse direction so as to reduce the turning radius.

Second Embodiment

With reference to FIGS. 8 to 10, the following explains a propeller power transmission device for a 1-engine, 2-shaft vessel according to a second embodiment of the present invention. FIG. 8 is a plan view schematically showing a vessel 2 equipped with a propeller power transmission device. FIG. 9 is a lateral view of the plan view of FIG. 8. As with FIG. 4, FIG. 10 is an expanded cross-sectional view schematically showing the propeller power transmission device with an engine.

A propeller power transmission device 1 a according to the second embodiment comprises an input shaft 9 a combined with a drive shaft 7 of an engine 3 via a coupling 8 made of an elastic joint; a pair of right and left output shafts 12 a and 13 a combined with the right and left propeller shafts 5 and 6 via couplings 10 and 11, respectively; an intermediate shaft 80 extending orthogonally to the input shaft 9 a; a driving bevel gear 81 fixed to the input shaft 9 a; a pair of driven bevel gears 82 and 83 which are rotatably supported by the intermediate shaft 80 and engaged with the driving bevel gear 81; a forward and reverse rotation clutch mechanism 84 for selectively connecting one of the driven bevel gears 82 and 83 to the intermediate shaft 80 so as to cause the intermediate shaft 80 to undergo forward or reverse rotation; and a set of bevel gears 85 and 86 for drivably connecting each of the output shafts 12 a and 13 a with each end of the intermediate shaft 80 intersecting with the output shaft 12 a or 13 a.

The intermediate shaft 80 may further comprise a pair of power transmission clutches 87 and 88 for transmitting or blocking, respectively, the power of the output shafts 12 a and 13 a.

In this case, brakes 87 a and 88 a are provided on the driven-sides of the pair of power transmission clutches 87 and 88, respectively, so as to control the intermediate shaft 80. The brakes 87 a and 88 a are constructed by fixing the inner drums, which have the driven-side friction plates of the clutches 87 and 88, to a gear case 4 a.

With this structure, the vessel moves forward or backward by establishing the forward or reverse engagement of the forward and reverse rotation clutch mechanism 84 and by establishing the engagement of the power transmission clutches 87 and 88. To make a turn with a small turning radius, one of the brakes 87 a and 88 a of the power transmission clutches 87 and 88 is brought into operation. The brake thus applied to the propeller provides a propulsive resistance, allowing the vessel to make a small-radius turn.

Third Embodiment

With reference to FIG. 11, the following explains a propeller power transmission device for a 1-engine, 2-shaft vessel according to a third embodiment of the present invention. Unlike the propeller power transmission device according to the second embodiment, the propeller power transmission device according to the third embodiment can be operated such that the output shaft 12 a undergoes forward rotation and the output shaft 13 a undergoes reverse rotation.

In the propeller power transmission device 1 b according to the third embodiment, the intermediate shaft rotatably held inside the gear case 4 b comprises a first intermediate shaft 80 a, a second intermediate shaft 80 b, and a third intermediate shaft 80 c. The first intermediate shaft 80 a rotatably supports a pair of driven bevel gears 82 a and 83 a engaged with a driving bevel gear 81 and comprises a forward and reverse rotation clutch mechanism 84 a for selectively connecting one of the driven bevel gears 82 a and 83 a to the intermediate shaft 80 a so as to cause the intermediate shaft 80 a to undergo forward or reverse rotation. The second intermediate shaft 80 b and the third intermediate shaft 80 c comprise a set of bevel gears 85 and 86 drivably connected to the output shafts 12 a and 13 a, respectively. The first intermediate shaft 80 a is connected to the second intermediate shaft 80 b and the third intermediate shaft 80 c via a gear train comprised of gears 90 to 93 containing transmission clutches 87A and 88A. A rotational direction inverting clutch mechanism 95 is provided at the butt joint of the second intermediate shaft 80 b and the third intermediate shaft 80 c. The rotational direction inverting clutch mechanism 95 is brought into operation only in the state where the power transmission of one of the power transmission clutches 87A and 88A is blocked.

In the third embodiment, the vessel moves forward or backward by establishing forward or reverse engagement of the forward and reverse rotation clutch mechanism 84 a and by establishing the engagement of the power transmission clutches 87A and 88A. To make a turn with a small turning radius, the propeller power transmission device is operated as follows, for example. With the forward and reverse rotation clutch mechanism 84 a engaged in forward or reverse mode, only the power transmission clutch 87A is engaged while blocking the power transmission clutch 88A and engaging the rotation direction inverting clutch 95. With this operation, rotation in a direction reverse to the rotation of the second intermediate shaft 80 b is transmitted to the third intermediate shaft 80 c via the bevel gears 95 a, 95 b and 95 c and the clutch drum 95 d fixed to the third intermediate shaft 80 c. As a result, the vessel makes a small-radius turn.

The first to third embodiments use a hydraulic wet clutch, but other clutches, such as a cone clutch, a dog clutch, or the like, can also be used.

Fourth Embodiment

With reference to FIGS. 12 to 17, the following explains a propeller power transmission device for a 1-engine, 2-shaft vessel according to a fourth embodiment of the present invention.

FIG. 12 is a lateral view showing the entire shape of a vessel equipped with a propeller power transmission device. As with the first to third embodiments, the propeller power transmission device according to the fourth embodiment has a so-called V-drive structure in which the propeller shafts 5 and 6 form a sharp-angled V-shape around the drive shaft of the engine 3.

FIG. 13 is a vertical cross-sectional view showing a propeller power transmission device. FIG. 14 is a partial cross-sectional view, taken along the line XIV-XIV of FIG. 13. FIG. 15 is a cross-sectional view of a propeller power transmission device, showing details, along the power transmission path.

As shown in FIGS. 13 and 15, the input shaft 9 b is supported by the bearings 100 and 101 provided inside the gear case 4 c. One end of the input shaft 9 b, which is connected to the drive shaft (not shown) of the engine 3 by means of spline engagement, projects from the gear case 4 c.

The input shaft 9 b rotatably holds a pair of driving, speed-changing gears having different diameters and different numbers of teeth: a small driving, speed-changing gear 102 and a large driving, speed-changing gear 103. The gear 102 is used for low-speed operation and the gear 103 is used for high-speed operation.

A speed-changing clutch mechanism 104 is provided between the input shaft 9 b and the gears 102 and 103 to transmit or block the power from the input shaft 9 b to the gears 102 and 103. The speed-changing clutch mechanism 104 is realized by a known wet multiplate hydraulic clutch, and is comprised of a hydraulic clutch 104 a for large deceleration and a hydraulic clutch 104 b for small deceleration.

These clutches 104 a and 104 b comprise a plurality of friction plates; a plurality of counter plates overlaid on the friction plates; a coil spring 106; and a pair of pistons 107 and 108. The friction plates are engaged with the inner drums 102 a and 103 a, which are respectively formed on the gears 102 and 103, in a manner such that they are slidable in the axis direction and incapable of rotating relative to the inner drums. The counter plates engage with the outer drum 105 with a H-shaped cross-sectional surface, which is fixed to the input shaft 9 b, in a manner such that they are slidable in the axis direction and incapable of rotating relative to the outer drum. The coil spring 106 is movably held in the axis direction of the input shaft 9 b to apply biasing forces to the counter plates and the friction plates to make them move away from each other. The pair of pistons 107 and 108 press the counter plates into the friction plates against the coil spring 106. A working oil supplied from the internal oil paths 109 and 110 formed inside the input shaft 9 b moves one of the pistons 107 and 108, thereby engaging a friction plate and a counter plate of one of the hydraulic clutches 104 a and 104 b. More specifically, operating the piston 107 drivably connects the input shaft 9 b and the driving, speed-changing gear 102, and operating the piston 108 drivably connects the input shaft 9 b and the driving, speed-changing gear 103.

Driven, speed-changing gears 111 and 112 are engaged with the large-diameter driving, speed-changing gear 102 and the small-diameter driving, speed-changing gear 103, respectively, and are combined with an axis 115 rotatably supported by the bearings 113 and 114 in parallel with the input shaft 9 b.

One end of the input shaft 9 b is sealed with an oil seal case 117 having a port (not shown) connected to a working oil supply tube 116. In the oil seal case 117, one end of the input shaft 9 b is provided with a plurality of annular grooves aligned in parallel, some of which communicate with one end each of the internal oil paths 109 and 110 extending inside the input shaft 9 b. The other ends of the internal oil paths 109 and 110 open to the piston chambers of the pistons 107 and 108 of the hydraulic clutches 104 a and 104 b. The port of the oil seal case 117 opens to the annular grooves communicating with the internal oil paths 109 and 110. Note that, for the sake of simplicity, the oil seal case 117 in the figure is connected to only one working oil supply tube 116, but the oil seal case 117 actually has a plurality of ports for supplying a working oil and a lubricating oil depending on the number of internal oil paths formed inside the input shaft 9 b, and each port is connected to the working oil supply tube and the lubricating oil supply tube (not shown).

As described, the driving, speed-changing gear 102 and the driven, speed-changing gear 111 comprise a large deceleration-side speed-changing gear train, and the driving, speed-changing gear 103 and the driven, speed-changing gear 112 comprise a small deceleration-side speed-changing gear train.

A bevel gear 118 is fixed to one end of the axis 115 on which the driven, speed-changing gears 111 and 112 are formed. The bevel gear 118 is engaged with a pair of right and left bevel gears 119 and 120. The bevel gears 118, 119 and 120 comprise a branch gear train for transmitting the power of the input shaft 9 b by dividing it into the right and left output shafts 12 b and 13 b. The axes 121 and 122 supporting the bevel gears 119 and 120 extend in a direction orthogonal to the shaft line of the input shaft 9 b.

Gears 123 and 124 are connected with the axes 121 and 122. Gears 125 and 126 engaged with the gears 123 and 124 are also engaged with the axes 127 and 128 by means of spline engagement. The axes 127 and 128 extend orthogonally to the shaft line direction of the input shaft 9 b. The axes 127 and 128 are linearly arranged along the same shaft line, with their ends opposite to each other.

The opposite ends of the axes 127 and 128 are provided with oil seal cases 129 and 130, respectively. The oil seal case 117 of the input shaft 9 b is positioned in the vicinity of the oil seal cases 129 and 130 of the axes 127 and 128. With this arrangement, in which the oil seal cases 117, 129 and 130 are located adjacently near the casing 4 c, the working oil supply tubes 116, 131 and 132 and the lubricating oil supply tube (not shown) can be arranged in a simple layout in the gear case 4 c.

The axes 127 and 128 are provided with forward and reverse rotation clutch mechanisms 133 and 134, respectively. The forward and reverse rotation clutch mechanisms 133 and 134 are similar to the speed-changing clutch mechanism 104, and include the forward rotation clutches 133 a and 134 a and the reverse rotation clutches 133 b and 134 b, respectively.

The forward rotation clutch 133 a transmits or blocks power from the axes 127 to the bevel gear 135 rotatably supported by the axes 127. The reverse rotation clutch 133 b transmits or blocks power from the axes 127 to the bevel gear 136, which is rotatably supported by the axes 127 opposed to the bevel gear 135.

Meanwhile, the forward rotation clutch 134 a transmits or blocks power from the axes 128 to the bevel gear 137, which is rotatably supported by the axes 128. The reverse rotation clutch 134 b transmits or blocks power from the axes 128 to the bevel gear 138, which is rotatably supported by the axes 128 opposed to the bevel gear 137.

The bevel gears 135 and 136, which are oppositely positioned, are engaged with the same bevel gear 139. This common bevel gear 139 transmits forward rotation to the output shaft 12 b when receiving power from the bevel gear 135, and transmits reverse rotation to the output shaft 12 b when receiving power from the bevel gear 136.

Similarly, the bevel gears 137 and 138, which are oppositely positioned, are engaged with the same bevel gear 140. The common bevel gear 140 transmits forward rotation to the output shaft 13 b when receiving power from the bevel gear 137, and transmits reverse rotation to the output shaft 13 b when receiving power from the bevel gear 138.

The bevel gear 139 is connected to one end of the rotation axis 141, which is rotatably held. A gear 142 formed on the other end of the rotation axis 141 is engaged with a gear 143, which is integrated with an output shaft 12 b. The output shaft 12 b has an insert hole through which the propeller shaft 5 penetrates, and is rotatably supported by the bearings 144 and 145 inside the gear case 4 b. The propeller shaft 5 penetrating through the insert hole of the output shaft 12 b is connected to the output shaft 12 b via the coupling 146.

The bevel gear 140 is connected to one end of the rotation axis 147, which is rotatably held. A gear 148 formed on the other end of the rotation axis 147 is engaged with a gear 149, which is integrated with an output shaft 13 b. The output shaft 13 b has an insert hole through which the propeller shaft 6 penetrates, and is rotatably supported by the bearings 150 and 151 inside the gear case 4 b. The propeller shaft 6 penetrating through the insert hole of the output shaft 13 b is connected to the output shaft 12 b via the coupling 152.

FIG. 16 is a hydraulic circuit diagram showing a propeller power transmission device according to a fourth embodiment. Working oil supply sources for the hydraulic clutches 104 a and 104 b, 133 a, 133 b, 134 a, and 134 b of the speed-changing clutch mechanism 104, and a pair of right and left forward and reverse rotation clutch mechanisms 133 and 134 are laid out as follows. A working oil is supplied from the oil reservoir 156 in the gear case, using the pump 155 driven by the engine 3. The working oil supply paths 157, 158, 159, 160, 161 and 162 contain, respectively, the following electromagnetic valves: electromagnetic proportional control valves 163, 164, 165, 166, 167 and 168. The pressure level of oil supplied from the pump 155 to the electromagnetic proportional control valves 163 to 168 is set to the clutch engagement pressure by the pressure control valve 169. The electromagnetic proportional control valve is capable of gradually increasing the pressure from 0 to the engagement pressure according to the current application value relative to the solenoid, allowing a corresponding hydraulic clutch to be gently engaged in a predetermined time after a clutch engagement signal (described later) is supplied. Note that the electromagnetic valve may be realized by a simple open/close valve or by a pressure control valve 169 constructed as a delay relief valve. The pressure control valve 169 is a relief valve. The oil passes through the pressure control valve 169 to be supplied as lubricating oil to the clutches 104 a and 104 b, 133 a, 133 b, 134 a, 134 b through the lubricating oil path 170. The pressure of the lubricating oil path 170 is also set to a predetermined value by the pressure control valve 171. In FIG. 16, the reference numeral 172 denotes an oil filter, and the reference numeral 173 denotes an oil cooler. Except for the pump 155, all valve components that are assembled into the hydraulic circuit may be contained together in the valve unit V that covers the wall opening 4X of the gear case 4 c. The working oil supply tubes 116, 131, 132 and the lubricating oil supply tube are connected to the supply oil paths 157, 158, 159, 160, 161 and 162, and to the lubricating oil path 170 provided inside the valve unit V.

The electromagnetic proportional control valves 163 to 168 may be operated by remote control by a joystick-type control lever 174 as shown in FIG. 17. The control lever 174 can also operate, by remote control, an electromagnetic actuator (not shown) for controlling the fuel spray amount or the throttle opening degree of the engine 3, as an output control device. The control lever 174 in the illustrated example functions as follows.

When shifted to the center, the control lever 174 sets a neutral state in which all electromagnetic proportional control valves 163 to 168 are deactivated, and all clutches are disconnected.

When the control lever 174 is inclined either forward or backward, a clutch engagement signal is emitted. Receiving the signal, a controller (not shown) activates the electromagnetic proportional control valve 164 so as to drivably engage the hydraulic clutch 104 b of the change clutch mechanism 104. Also, according to the selected direction, one of the electromagnetic proportional control valves 165 to 168 is activated to drivably engage the forward and reverse rotation clutch mechanisms 133 or 134. This activates an electromagnetic actuator (not shown), which controls the fuel spray amount or the throttle opening degree according to the degree of the forward or reverse inclination. In this state, the engine rotation rate increases from the idling state to the maximum rotation rate while the propeller shafts 5 and 6 are rotating forward or reverse. As a result, the vessel moves forward or backward at the desired speed.

The traveling direction of the vessel being driven in forward or reverse can be changed without operating a steering wheel by inclining the control lever 174 to the left or right. At this time, the proportional control valves 165 to 168 are controlled so that the clutches on the inner side of rotation of the forward and reverse rotation clutch mechanisms 133 and 134 are once turned off so as to ease the switching shock, and the clutches on the other side are engaged as the lever is again moved to the left or right. This allows to the vessel to make a relatively steep turn. Note that the ports of the electromagnetic proportional control valves 165 to 168 interposed in the working oil supply paths 159 to 162 connected to the forward and reverse rotation clutch mechanisms 133 and 134 open depending on the degree of the left or right inclination of the control lever 174; therefore, the engagement pressure can be adjusted by changing the inclination angle. This allows the turning radius to be adjusted.

The control lever 174 further comprises, on the top of the handle, a speed-changing button switch 175 operable by the thumb. The speed-changing button switch 175 serves to switch the clutch of the speed-changing clutch mechanism 104. The speed-changing button switch 175 deactivates the electromagnetic proportional control valve 164 interposed in the working oil supply path 158 connected to the hydraulic clutch 104 b of the speed-changing clutch mechanism 104, and activates the electromagnetic proportional control valve 163 interposed in the working oil supply path 157 connected to the hydraulic clutch 104 a. With this structure, power is constantly transmitted from the small deceleration-side speed-changing gear train 103-112 to the large deceleration-side speed-changing gear train 102-111. For example, when ballast water is poured into the vessel to purposely make a large wave for wakeboarding, the vessel can be driven at a very low speed to avoid a large load on the engine 3. The speed-changing button switch 175 is disposed on the control lever 174 in the illustrated example, but may also be disposed on the control panel in the vicinity of the control lever 174.

The movement of the control lever 174 can be restricted by a brake plate 176 as shown in the figure, so that it can cause a turn only in the forward or reverse rotation by the right and left movement of the control lever within the low-speed region L. In this way, the vessel is prevented from making such a turn in the high-speed forward movement region F or the high-speed backward movement region R.

Note that if the vessel makes a slow turn only, as it is not required to make a steep turn, the following arrangement can be adopted. The forward and reverse rotation clutch mechanism of only one of the right and left forward and reverse rotation clutch mechanisms 133 and 134 is cut off when the control lever 174 is inclined to the left or right end so as to stop the operation of the propeller shaft on the inner side of rotation. With this arrangement, power is transmitted only by the other reverse rotation clutch mechanism, and only the propeller shaft on the outer side of rotation is driven.

Fifth Embodiment

With reference to FIGS. 18 to 20, the following explains a propeller power transmission device according to a fifth embodiment of the present invention. FIG. 18 is a vertical cross-sectional view showing a propeller power transmission device. FIG. 19 is a partial cross-sectional view, taken along the line XIX-XIX of FIG. 18. FIG. 20 is a cross-sectional view of the propeller power transmission device, showing details, along a power transmission path.

The fifth embodiment is a modification of the fourth embodiment. Their major difference can be clearly seen by comparing FIG. 20 and FIG. 15. The forward reverse rotation clutch mechanisms 233 and 234 of the present embodiment form a different clutch structure in the gear case 4 c from that of the fourth embodiment.

In the fifth embodiment, the gears 223 and 224 are supported by the axes 221 and 222 that rotatably support the left and right bevel gears 119 and 120, which engage with the bevel gear 118. The gears 223 and 224 are incapable of rotating relative to the axes 221 and 222. Gears 235 and 237 are rotatably supported by the axes 221 and 222. The gears 235 and 237 on the axes 221 and 222 receive power through the forward rotation hydraulic clutches 233 a and 234 a of the forward and reverse rotation clutch mechanisms 233 and 234.

The gears 223 and 224 engage with gears 225 and 226, which are arranged in parallel with the axes 221 and 222, while being supported by the axes 227 and 228 rotatably held inside the casing 4 c. The gears 225 and 226 are incapable of rotating relative to the axes 227 and 228. Gears 236 and 238 are rotatably supported by the axes 227 and 228. The gears 236 and 238 on the axes 227 and 228 receive power through the reverse rotation hydraulic clutches 233 b and 234 b of the forward and reverse rotation clutch mechanisms 233 and 234.

The gears 235 and 236 constantly engage with a common gear 239. The gears 237 and 238 also constantly engage with a common gear 240. The gears 239 and 240 are rotatably supported by the axes 241 and 247, while being incapable of rotating relative to the axes 241 and 247. The output shafts 12 b and 13 b receive power from the bevel gears 270 and 271 fixed, respectively, to the ends of the axes 241 and 247, through the bevel gears 272 and 273, the gears 242 and 248, and the gears 243 and 249. The output shafts 12 b and 13 b are connected to the propeller shafts 5 and 6 via couplings 246 and 252, respectively.

As with the case above, the oil seal cases 217, 229 and 230 are also adjacently positioned in the fifth embodiment, hence the working oil supply tube and the lubricating oil supply tube have a simple layout. In the fifth embodiment, the gear pump 255 for supplying the working oil and the lubricating oil is connected to the axes 227. The gear pump 255 may be connected to any axis that is constantly driven in the gear case 4 c.

Sixth Embodiment

With reference to FIGS. 21 and 22, the following explains a propeller power transmission device according to a sixth embodiment of the present invention. For the sixth embodiment, a speed-changing clutch mechanism is mounted to the propeller power transmission device of the first embodiment.

A speed-changing clutch mechanism 300 is formed on the input shaft 9. The speed-changing clutch mechanism 300 comprises a low-speed hydraulic clutch 300 a and a high-speed hydraulic clutch 300 b. The low-speed hydraulic clutch 300 a transmits or blocks power from the input shaft 9 to the driving, speed-changing gear 301, which has a small diameter and is rotatably supported by the input shaft 9. The high-speed hydraulic clutch 300 b transmits or blocks power from the input shaft 9 to the driving, speed-changing gear 302, which has a large diameter and is rotatably supported by the input shaft 9.

The driving, speed-changing gear 301 and the driving, speed-changing gear 302 engage with driven, speed-changing gears 303 and 304, respectively. The driven, speed-changing gears 303 and 304 are supported by an axis 305 rotatably held inside the casing 4. The driven, speed-changing gears 303 and 304 are incapable of rotating relative to the axis 305.

A gear 20A is supported by an axis 305, while being incapable of rotating relative to the axis 305. The gear 20A is engaged with the gear 21 and the gear 22. The power transmission paths from the gear 20A to the output shafts 12 and 13 are the same as those between the gear 20 to the output shafts 12 and 13 of the first embodiment; therefore, a detailed explanation is omitted here. 

1. A propeller power transmission device for a 1-engine, 2-shaft vessel in which an engine drive shaft has a pair of right and left propeller shafts, the propeller power transmission device comprising: a gear case; an input shaft that is supported by a bearing inside the gear case and that is connected to the drive shaft of the engine via a coupling; a pair of right and left output shafts that are supported by bearings inside the gear case and that are connected to the right and left propeller shafts, respectively, via couplings; and a gear train contained in the gear case for transmitting power of the input shaft to the pair of output shafts via a clutch mechanism; wherein the clutch mechanism includes a forward and reverse rotation clutch mechanism for switching the gear train so as to change rotation of the output shaft between forward and reverse.
 2. A propeller power transmission mechanism according to claim 1, wherein the gear train is comprised of a plurality of cylindrical gears and one or two cone gears, and the shaft lines of the right and left propeller shafts are inclined by the cone gear(s) relative to the shaft line of the engine drive shaft.
 3. A propeller power transmission device according to claim 1, wherein the gear train comprises: a driving bevel gear that is fixed to the input shaft; a pair of driven bevel gears that are rotatably supported by an intermediate shaft extending orthogonally to the input shaft and that engage with the driving bevel gear; and a set of bevel gears for drivably connecting each of the output shafts with each end of the intermediate shaft substantially intersecting with the output shafts; wherein the forward and reverse rotation clutch mechanism selectively connects one of the driven bevel gears to the intermediate shaft so as to cause the intermediate shaft to undergo forward or reverse rotation.
 4. A propeller power transmission device according to claim 3, wherein the clutch mechanism is provided on the intermediate shaft and includes a pair of power transmission clutches for transmitting or blocking power to the output shafts.
 5. A propeller power transmission device according to claim 4, wherein each driven side of the power transmission clutches is provided with a brake for controlling the intermediate shaft.
 6. A propeller power transmission device according to claim 4, wherein the intermediate shaft comprises a first intermediate shaft, a second intermediate shaft and a third intermediate shaft; the first intermediate shaft is provided with a forward and reverse rotation clutch mechanism that rotatably supports the pair of driven bevel gears that engage with the driving bevel gear and selectively connects one of the driven bevel gears to the first intermediate shaft so as to cause the first intermediate shaft to undergo forward or reverse rotation; the second intermediate shaft and the third intermediate shaft include a set of bevel gears drivably connected to the respective output shafts; the first intermediate shaft connects to the second intermediate shaft and the third intermediate shaft via a gear train containing the power transmission clutches; and the clutch mechanism includes a rotational direction inverting clutch mechanism which rotates the second intermediate shaft and the third intermediate shaft in opposite directions at a butt joint of the second intermediate shaft and the third intermediate shaft, the rotational direction inverting clutch mechanism being brought into operation only in a state where power transmission of one of the power transmission clutches is blocked.
 7. A propeller power transmission device according to claim 1, wherein the gear train includes two or more speed-changing gear trains, each of which includes a driving, speed-changing gear and a driven, speed-changing gear, and the clutch mechanism further includes a speed-changing clutch mechanism for transmitting or blocking power by selecting one of the speed-changing gear trains.
 8. A propeller power transmission device according to claim 7, wherein each driving, speed-changing gear is provided on the input shaft, and each driven, speed-changing gear is provided on a rotation axis disposed in parallel with the input shaft.
 9. A propeller power transmission device according to claim 1, wherein the forward and reverse rotation clutch mechanism is comprised of hydraulic clutches; the propeller power transmission device further comprising a control lever for operating, by remote control, an output control device of the engine in conjunction with electromagnetic valves for controlling supply of a working oil to the hydraulic clutches.
 10. A propeller power transmission device according to claim 9, wherein the speed-changing clutch mechanism is comprised of hydraulic clutches; the propeller power transmission device further comprising a switch for activating and deactivating the electromagnetic valves for controlling the supply of a working oil to the hydraulic clutches.
 11. A propeller power transmission device according to claim 7, wherein the gear train includes a branch gear train for transmitting power of the input shaft by dividing it into the right and left output shafts; the speed-changing clutch mechanism is disposed closer to the input shaft than the branch gear train in the gear train; and the forward and reverse rotation clutch mechanism is disposed closer to the output shaft than the branch gear train in the gear train.
 12. A propeller power transmission device as set forth in claim 11, wherein each of the forward and reverse rotation clutch mechanism and the speed-changing clutch mechanism is comprised of hydraulic clutches, each axis for supporting each hydraulic clutch is provided with an oil seal case having a port connected to a working oil supply source on one end, and at least one internal oil path for supplying a working oil to the hydraulic clutch; the hydraulic clutches of the forward and reverse rotation clutch mechanism are supported by a pair of axes linearly arranged along a shaft line with their oil seal cases oppositely arranged; the hydraulic clutches of the speed-changing clutch mechanism are supported by an axis disposed orthogonally to the shaft line on which the axes for supporting the hydraulic clutch of the forward and reverse rotation clutch mechanism are arranged, with its oil seal case disposed in the vicinity of the oil seal cases of the axes supporting the hydraulic clutches of the forward and reverse rotation clutch mechanism.
 13. A propeller power transmission device according to claim 1, wherein the forward and reverse rotation clutch mechanism separately operates the individual output shafts to undergo forward or reverse rotation. 